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  1. #1
    Join Date
    Dec 2013
    Posts
    8

    Default pump vibration transferred through concrete

    Good day you all.

    I have a water pump with a pressure switch installed on the flat roof of my concrete/block house. on the discharge side of the pump is a PVC entering to the house through the concrete/block system.

    The problem is that its installed above the master bedroom, and when ever someone turns a faucet at night it wakes me up. take note when I go to the roof the pump sound is very minimal. in fact the noise I hear in the master bedroom is 3x the noise of the pump

    This is what I think:
    1- The pump is fastened with galvanized bolts; thus it transfers the vibration; so I removed the bolts and placed a thick waffle pads ( HVAC grade ). Any better ideas?

    2- How can I eliminate vibration from the PVC entering through the concrete block wall? I thought of clamping a rubber hose as an intermediate so the setup will be Pump>>short PVC >>> Rubbrized hose >>> PVC to the house
    Will this work? will my solution last long enough or I will be replacing the rubber hose every year or so?

  2. #2
    Join Date
    Jul 2010
    Location
    SoCal
    Posts
    5,081

    Default Re: pump vibration transferred through concrete

    You have the right approach, with your "bumpers", give it a try and see if there's an improvement.

    Another idea is to move the darn pump.

  3. #3
    Join Date
    Aug 2007
    Location
    Maryland
    Posts
    1,159

    Default Re: pump vibration transferred through concrete

    The pads are a good idea. The idea Is to isolate the source of the vibration from the structure. As you know the vibrating structure is worse than the airborne sound. Commercial equipment like large HVAC equipment or generators often use vibration isolators the keep the sound out of the structure. They are a spring like device that keeps the bolted down equipment from direct contact with the structure. They might be overkill in your situation, but no direct fastener to the roof will help.
    Some sound insulation below the pump might help. If the pump was mounted on a platform with insulation below it would absorb some of the airborne sound before it gets into the roof.
    The rubber hose on the pipe would isolate the vibration too. I've seen similar setups on pipes, but don't know what products are available. Forced air furnaces always have a soft connection to the main duct for that reason. The rubber may need protection from UV, but it should last. A plumbing supply store may have products specifically for the situation.

  4. #4
    Join Date
    Dec 2007
    Location
    Tennessee
    Posts
    1,381

    Default Re: pump vibration transferred through concrete

    Currently the bolts that secure the pump to the roof are causing the roof to vibrate, turning it into a large speaker, that is why it is louder inside the house than outside.

    Waffle board will help, but you will still have a direct connection of the pump to the ceiling via the bolts. You need to get an isolation pad or isolation feet for the pump. Not sure if you can find a pad that fits but isolation feet should be available. These would bolt to the roof of the house. there will be a rubber block bonded to the pad that the stud sticks out of that bolts to the roof. The there would be another steel pad on top of the block and a stud sticking out of that that you mount the pump foot on. You would need one for each foot.

    Gel filled rubber blocks would work even better but I don't know if any are available.

    As for the PVC pipe, the hole in the roof should be at least 1/4" larger than the pipe all around it. A rubber seal like those used on roof vents would go around the pipe and glued to the roof to keep rainwater out. Or you could just fill the gap with silicone caulk.

    http://www.soundproofcow.com/skin/co...t_feet_pds.pdf These will help but I don't think they are the best answer, but they might be good enough.

    http://www.acousticalsolutions.com/isolation-mounts this is more what I had in mind. Pricy though.
    Last edited by keith3267; 12-06-2013 at 03:17 PM.

  5. #5
    Join Date
    Dec 2013
    Posts
    8

    Default Re: pump vibration transferred through concrete

    Thank you all for the great tips!

  6. #6
    Join Date
    Jan 2008
    Posts
    1,096

    Default Re: pump vibration transferred through concrete

    You sometimes see a "U" shaped section plumbed into piping for no apparent reason. This allows for there to be movement of the piping, usually to allow for expansion but also to reduce vibrations With a 1" or less PVC pipe, and 'offset bend' like this about 1 ft or so in length should eliminate most of the vibration transfer. Something was already said of PVC and the effects of UV radiation and you should look into that. It not only deteriorates the pipe more rapidly, but it releases some nasties into the water inside the pipe which you don't want to be drinking. You might want to put a cover over the pump and piping.

    If nothing else helps enough with the vibration, resort to brute force to help with the rubber used for isolation. Place the rubber pads on the roof, and solidly bolt the pump to a concrete slab you form and pour to fit it's size and set that whole thing on the rubber pads. The added mass will inertially dampen vibrations and movement of the pump considerably. Last resort you could move the pump to where it can vibrate all it wants to without touching the house.

    Phil

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